An historical and philosophical account of the barometer, or, weather-glass, wherein the reason and use of that instrument, the theory of the atmosphere, the causes of its different gravitation are assigned and explained. And a modest attempt from thence made towards a rational account and probable judgment of the weather / By Edward Saul, A.M.

  • Saul, Edward, 1677-1754.
Date:
1766
Catalogue details

Licence: Public Domain Mark

Credit: An historical and philosophical account of the barometer, or, weather-glass, wherein the reason and use of that instrument, the theory of the atmosphere, the causes of its different gravitation are assigned and explained. And a modest attempt from thence made towards a rational account and probable judgment of the weather / By Edward Saul, A.M. Source: Wellcome Collection.

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    [ 16 ] or 33 Inches. This was the State in which !Torricelhus framed and left the Barometer (from him in the Writings of the modem Philofophers ufually called the Torricellian Experiment) and which indeed, was only applied at the find to prove the general Gravitation of the Air, without drawing any other Philofophical Conclufions from it. The Honour of ftill farther improving the Barometer, and of bringing it to a greater D egree of ExaCtnefs and Perfection, was referved for the noble and fagacious Mr. Boyle ; who, by frequent Obfervations and Experiments, was the fir ft that convinced the World of the great Inequality in the Gravitation of the Air at different Times and Places; and that contrary to the received Opinion, the Preffure of the Air was grea?- eft, when it was moil clear and ferene, and leaft, when it was moft charged with Clouds and Vapours; becaufe in fair Weather, the Mercury ufually rofe and kept up to the Eleight of 29 4 or 30 Inches ; but in changeable, rainy, or ftormy Weather, ufu¬ ally fettled to 29, 28 i and even fometimes below 28 Inches. And from hence not only by obferving a regular Correfpondence betwixt the Rife and Fall of the Mercury, and the Changes of the Weather; hut by marking and ad-, jufting the precife Limits to both, upon a graduated Plate of Brafs, on each Side of the